Check That Expression Causes Expected Warnings

atExpectWarnings

Description

Evaluate an expression and verify that it causes the warning messages that it should.

Usage

atExpectWarnings(expr, expected = ".")

Arguments

expr	An expression to evaluate. It will be taken literally, as in system.time().
expected	Regular expressions that should match the expected warning messages. See regexpr for the syntax. "." means to match any warning.

Value

TRUE if the expression evaluates to TRUE and causes the expected warnings. Otherwise a list containing a description of the problem. This sort of output is expected by assertionTest.

Note

If an expression is expected to cause both warnings and an error then wrap it first in atExpectStop and then in atExpectWarnings.

See Also

This is written to be used in test files run by assertionTest, which will report a test failure if there are any warnings not caught by a call to atExpectWarnings().

Examples

## Not run: 
# First two examples should return TRUE
atExpectWarnings({
    warning("Comparing integer and complex number")
    1L == (1+0i)},
    expected = "integer.*complex")
atExpectWarnings(
    atExpectStop({warning("Hmm, possible problem")
    stop("Oops")},
    expected="Oops"),
    expected = "Hmm")
# Next one should describe lack of expected warning
atExpectWarnings(all(is.finite(log(3:4))), "NaNs produced")
# Run example test files in assertionTest/test-ex
assertionTest(system.file(package="assertionTest", "test-ex", "mixed.t",
    mustWork=TRUE))

## End(Not run)

Package assertionTest version 6.1.5-18
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